Stuff like IP address for geotargeting, the phone's UDID (a numeric identifier) for frequency capping and conversion tracking, the name of the app for obvious r

Stuff like IP address for geotargeting, the phone's UDID (a numeric identifier) for frequency capping and conversion tracking, the name of the app for obvious reporting reasons, and whether the ad's been viewed or clicked, again for obvious reporting reasons. Same as anybody else in the space.